Although the ZIP file format it is a proprietary, de-facto standard by PKWARE Inc., ZIP files are ubiquitous on the Internet and thus on many platforms today. The J2SE API provides a well known package java.util.zip with classes like ZipInputStream, ZipOutputStream and ZipFile for easy access to ZIP compatible files. However, this package has some limitations/disadvantages:

* Sun's implementation uses the character set UTF-8 (eight bit Unicode character set) for entry names and comments instead of CP437 (the genuine IBM-PC character set) as used by the de-facto standard PKZIP from PKWARE. As a result, you cannot read or write ZIP files with international entry file names such as "t?cht.txt" in a ZIP file created by a (southern) German.
* You need to use an additional API (the package java.util.zip) if your application needs to support ZIP compatible files in addition to ordinary files and directories, thereby significantly inflating your code and adding unnecessary complexity (which adds bugs, bugs, and even more bugs).
* You can either read or completely write ZIP compatible files, but you cannot just update individual entries.
* The classes do not support the concept of a directory, which you may want to create, modify, list or delete.
* You cannot browse a ZIP compatible file with a JFileChooser or FileSystemView.
The TrueZIP Library has been developed to overcome these limitations/disadvantages.

Scriptella is an ETL (Extract-Transform-Load) and script execution tool. Its primary focus is simplicity. It doesn't require the user to learn another complex XML-based language to use it, but allows the use of SQL or another scripting language suitable for the data source to perform required transformations.

Dozer is a powerful, yet simple Java Bean to Java Bean mapper that recursively copies data from one object to another. Typically, these Java Beans will be of different complex types. Dozer supports simple property mapping, complex type mapping, bi-directional mapping, implicit-explicit mapping, as well as recursive mapping. The mapper is used any time you need to take one type of Java Bean and map it to another type of Java Bean. Most field mapping can be done automatically by Dozer using reflection, but any custom mapping can be predescribed in XML format.

NailGun: Insanely Fast Java
NailGun is a client, protocol, and server for running Java programs from the command line without incurring the JVM startup overhead. Programs run in the server (which is implemented in Java), and are triggered by the client (written in C), which handles all I/O.

JoSQL provides SQL capabilities for querying, ordering, and grouping of collections of Java objects. It allows a SQL statement to be applied to the collection of objects and the matching set returned, ordered and grouped. It should be used when a RDBMS is either too heavyweight or too impractical.

NativeCall lets you call native methods from Java without JNI code. With NativeCall, you can call all methods implemented in any DLL. It supports structs, Strings, primitive types (int and boolean), byte and char arrays and output parameters. NativeCall is implemented for the Windows platform.